Fig. 5.

Effect of IL-1β on intracellular Ca²⁺ concentration ([Ca²⁺]_i) in cultured human proximal tubule cells. a Representative trace of Fura-2 Ca²⁺ imaging which shows that IL-1β caused a transient rise in [Ca²⁺]_i. b The IL-1β-induced rise in [Ca²⁺]_i did not occur in the presence of IL-1ra, although the effect of IL-1β was still observed after washing out IL-1ra. The doses of IL-1β and IL-1ra were 15 pg/ml and 20 ng/ml, respectively. Each trace was recorded with separate cells. c Summarized data showing [Ca²⁺]_i under the control condition (n = 24) and [Ca²⁺]_i in response to IL-1β (n = 24), IL-1ra (n = 10), and IL-1β in the presence of IL-1ra (n = 10). *P < 0.05, significantly different compared with the control